The method of stabilizing foods with an antioxidant

ABSTRACT

A synergistic antioxidant composition comprising a phenolic-type antioxidant and a degraded protein, and a method of stabilizing food products against oxidation therewith. BHA, BHT, and Alpha tocopherol are particularly suitable phenolic-type antioxidants for use in such compositions. Autolyzed yeast or hydrolyzed vegetable protein are particularly effective degraded proteins for such use in compositions for protecting food products, permitting marked reductions in the concentrations of the phenolic-type antioxidants.

United States Patent 1191 Bishov et al.

[ Dec. 3, 1974 THE METHOD OF STABILIZING FOODS WITH AN ANTIOXIDANT [75] Inventors: Solomon J. Bishov; Albert S.

Henick, both of Framingham, Mass.

[22] Filed: Apr. 9, 1973 [2]] Appl. No.: 349,588

52 US. Cl 426/328, 426/179, 426/183, 426/228 51 Int. Cl A231 3/34 [58] Field of Search 426/228, 62, 72, 181, 183, 426/328, 204; 252/404 [56] References Cited UNITED STATES PATENTS 2,928,740 3/l960 Rosenthal et al. 426/62 3,278,308 10/1966 Mam) 426/228 3,448,010 6/1969 Pomper et al. 426/62 3,637,772 1/1972 Klaui et al. 426/228 Primary ExaminerA. Louis Monacell Assistant ExaminerCurtis P. Ribando Attorney, Agent, or Firm-Eugene E. Stevens; Chari C. Rainey; Lawrence E. Labadini ABSTRACT A synergistic antioxidant composition comprising a phenolic-type antioxidant and a degraded protein, and a method of stabilizing food products against oxidation therewith. BHA, BHT, and a-tocopherol are particularly suitable phenoliotype antioxidants for use in such compositions. Autolyzed yeast or hydrolyzed vegetable protein are particularly effective degraded proteins for such use in compositions for protecting food products, permitting marked reductions in the concentrations of the phenolic-type antioxidants.

2 Claims, N0 Drawings THE METHOD OF STABILIZING FOODS WITH ANTIOXIDANT The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to us of any royalty thereon.

BACKGROUND OF THE INVENTION This invention relates to synergistic antioxidant com positions and to a method of stabilizing food materials therewith. More particularly, the invention relates to reducing the concentration of well-known and widely used synthetic or naturally occurring phenolic-type antioxidants by the employment in conjunction therewith of a synergistic antioxidant material'derived from natural proteinaceous materials.

It has been customary in the processing of a great many foods, which are to be stored for a fairly long period of time between their manufacture and their ultimate consumption, to add small quantities of antioxidants to the foods during their manufacture, or in some cases to take advantage of naturally occurring antioxidants contained in one or more of the ingredients used in the manufacture of the foods. Among the more frequently employed antioxidants for this purpose are members of the phenolic group of anti-oxidants, some of thelmoreefficient of which are synthetic. BHA and BHT are two of the more often antioxidants of this type. Although they are synthetic, their use is permitted by the Food and Drug Administration provided their concentrations in foods do not exceed certain values. The tocopherols, especially a-tocopherol, have also been permitted in foods..These antioxidants occur'naturally in a number of food materials, notably vegetable oils. However, in general, the latter antioxidants are not as effective as BHA, so that this antioxidant material has come to be probably the most highly favored antioxidant for stabilizing food products against oxidation.

' haps more from the standpoint of the possibility that synthetic materials in contrast to .naturally occurring materials may be more. conducive to abnormalities in growth and development of human beings, or of ani- I mals which are used as sources of food products. Whatever the reason for the concern, it appears desirable insofar as possible to reduce the concentrations. of such antioxidants as the phenolics, such as BHA or BHT, or

even of such naturally occurring antioxidants as the to-.

provide an antioxidant composition comprising a phenolic-type antioxidant, the antioxidant action of which is synergized by means of a composition derived from naturally occurring food materials so that the concentration of the phenolic-type antioxidant may be reduced below that which is normally required for good tion with the appended claims.

I SUMMARY The objects of the invention are accomplished by combining a protein derivative material prepared from yeast by autolysis thereof or from a plant or vegetable protein, such as soy bean protein, by acid hydrolysis thereof, with a phenolic-type antioxidant and incorporating such a combination in a food product which, in the absence of the antioxidant composition, would be subject to rapid oxidation in the presence of air. In gen eral, because of the synergistic action of the protein derivative material, it is notnecessary to employ nearly so high a concentration of the phenolic-type antioxidant in the food product as when there is substantially no added protein derivative, particularly of. the autolyzed yeast protein type or the hydrolyzed vegetable protein type, present in the food. v

. Autolyzed yeast proteins and hydrolyzed vegetable proteins have proven very useful in the development of special flavors simulating meat flavors of various types as well as other desirable flavors. Since these protein derivatives are prepared from natural sources which are quite edible and nutritious, there appears to be no reason why they would not be permissible in foodproducts along with small concentrations of antioxidants which have been proven to be effective and which are permitted to be addedto foods or to be naturally pres ent in foods in concentrations up to certain legally acceptable concentrations, especially 'whentheir presence along with the phenolic-type antioxidant makes possible an appreciable reduction in the concentration of the phenolic-type antioxidant due to the synergistic action of the protein derivative on the phenolic-type antioxidant, without excessive-loss of stabilizing-effecton the food involved.

Butylated hydroxyanisole (abbreviated herein and generally referred to as BHA) is a mixture of isomers of 4-hydroxyanisole having a tertiary butyl group substituted in the benzene ring at the 2- or 3- position.

of 4-hydroxytoluene having a tertiary vbutyl group substituted in the benzene ring at the 2- or 3- position.

L Alpha-tocopherol (a-tocopherol) is 5, 7, 8- trimethyltocol which occurs naturally in substantial concentrations in wheat germ oil. It is a phenolic type antioxidant and is also recognized as being Vitamin E or'the most important constituent of Vitamin B.

Up to 0.02 percent by weight of BHA is permitted in food products by the Food and Drug Administration. The antioxidant effect of BHA increases as the concentration thereof increases up to 0.02 percent, then levels off for higher concentrations. Approxima ttely l0 percent by weight of autolyzed yeast protein is required to plus percent autolyzed yeast protein. It is apparent, I

therefore, that a synergistic effect is obtained when the degraded protein is used in combination with the BHA, thus permitting a substantial (about a four-fold) decrease in the concentration of the BHA required to provide a given degree of antioxidant protection. Similar results have been obtained with hydrolyzed vegetable protein as the degraded protein serving as a synergist for BHA. Quite similar synergistic effects have been found when protein derivative material from autolyzed yeast protein or hydrolyzed vegetable protein has been combined with BHT or a-tocopherol as with BHA. v

in general, from about 3 percent to about l0 percent by weight of the protein derivative material is preferably used in combination with either BHA or BHT or a-tocopherol to synergize the antioxidant effect of the BHA or BHT or the a-tocopherol, although other concentrations from about 0.5 percent to about 50 percent by weight may be used, if .found desirable, in order to decrease the concentration of the phenolic-type antioxidant used to accomplish protection of food products against oxidation. a

In general, the invention isapplicable to any concentration of a phenolic-type antioxidant in a food product from about 0.0005 percent up to about 0.05 percent, but normally concentrations of such antioxidants above those approved by the US. Foodand Drug Administration for use in human foods will not be used.

Throughout the specification and claims the percentages of the antioxidant materials are based on the weight of oxidation-susceptible oil with'which the antioxidant material is used.

DESCRIPTION OF THE PREFERRED l EMBODIMENT EXAMPLE I The Nestle Co., Inc. were used. each in combination with BHA in the form of butyl hydroxyanisole manufactured by Distillation Products Industries Division. Eastman Chemical Products, Inc., in an emulsion with tocopherol-free corn oil manufactured by Distillation Products Industries Division, Eastman Chemical Products, Inc. and carboxy-methyl-cellulose (CMC) manufactured by Hercules Manufacturing Co. as an inert matrix, each emulsion being shell frozen and then freeze dehydrated prior to oxidation studies on the freeze-dried mixture to determine the induction period. Individual samples were prepared by adding (in succession) to a blender cup 50 ml water, the antioxidant mat e r ial (Bl-lA as required, t h e synergistic antioxidant material (AYP or HVP) as required, 1 g. CMC, and dropwise with intermittent mixing in a blender l g. of tocopherol-free corn oil. Total solids in the emulsion were adjusted to 15 percent. The final mixture was blended for 2 minutes, transferred to a 250 ml round bottom flask, shell frozen, and freeze dehydrated. The freeze dehydrated emulsions were individually ground in a sharp-bladed Waring blender to produce light, fluffy flakes of large surface area and having densities of about 0.1 to 0.2 g per cc. on which the oxidation studies were run.,The oxidation of each sample was carried out in a 250 ml round bottom flask under an atmosphere of air at 655C. The flasks were closed with rubber serum stoppers. Oxygen in the headspace was Autolyzed yeast protein (AYP) in theform of comcial l-lVP manufactured by- Food Ingredients Division,

determined periodically by gas, chromatography according to the method of the inventors of the present application published in the Journal of the American Oil Chemists Society, Vol. 43, page 477. The induction period (I.P.) was taken as the time (in hours) at which percent of the original oxygen in the'headspace had been consumed. Table 1 shows the induction periods for the various samples, the BHA and AYP or"% HVP being in terms of weight percentage of the towpherol-free corn oil. The synergism of the combination of BHA and either AYP or HVP is expressed as a percentage, represented by Syn. of the observed effect due to synergism, and is calculated from the equation:

Syn. =[(MC)(PC)-(AC)]/(M C) in which v M the LP. of the combination of antioxidants P the LP. of the phenolic (Bl-IA) antioxidant A the LP. of the autolyzed yeast protein (AYP) or the hydrolyzed vegetable protein (HVP) C the [.P. ofthe control (no antioxidant) Each I.P. value represents the average of duplicate determinations. The mean value is the average value for all of the Syn. percent values for a given combination of Bl-IA with either AYP or HVP.

TABLE 1 AYP I 0 10 25 5 0 BHA LP. LP. Syn. 'LP. Syn. LP. Syn.

0 39 131 200 0.005 59 221 as 267 47 32s 37 0.010 64 22s 46 30s 53 370 44 0.020 as 307 44 447 6| 49s 52 Mganjvn. 47.0

% HVP 0 l0 25 .50

BHA LP. Syn. 0i. |.P. ,s n.'% LP. s n. /.1

0 14 00 123 m 0.005 '42 r89 40 275 414 37.7 52 0.010 96 253 v 34 .333 40 440 47 0.020 H6 386 52 45s 53 40s EXAMPLE 11 a-tocopherol in combination with either AYP or HVP was used to stabilize corn oil from which the naturally occurring tocopherols had been removed in a trated by means of detailed examples in which synergistic antioxidant compositions comprised either BHA or BHT or a-tocopherol as phenolic-type antioxidants and HVP or AYP as protein derivative materials acting as 5 synergists for the phenolic-type antioxidants, it is to be manner similar to the use of BHA described in Example understood that other phenolic-type antioxidants may I. Table 2 shows the induction periods (in hours) for be used in a similar manner. For example, other tothe various samples in which the concentrations of copherols, ofwhich several are known and which have a-tocopherol and AYP or HVP were varied. The synerantioxidant properties, may be similarly used in combigism of the combinations of antioxidants was calcu- 10 nations with HVP or AYPas synergists. Although relalated in the same manner as in Example I. tively few of the known antioxidants are approved by TABLE 2 AYP 0 10 50 %a-tocopherol LP. l.P. Syn.% LP. Syn.% LP. Syn.%

- Mean Svn. 37.0

% HVP 0 10 25 50 %a-tocopherol l.P. l.P. Syn.% LP. Syn.% LP. Syn.%

0.02 27 160 39 207 37 238 0.04 '33 195 47 227 40 277 38 0.06 52 237 4'9 257 40 260 26 0.08 34 162 204 32 242 28 Mean Syn. 37.0

EXAMPLE lll the Food and Drug Administration for addition to food 7 V g I J 3 5 products, any such antioxidant materials of the phenol- Butylated hydroxytoluene (BHT) in combination ic-type which now or in the future may be approved for with either AYP or-HVP was used to stabilize tocouse in combination with food products are contempherol-free corn oil in a manner similar to the use of plated as being within the scope of the present inven- BHA described in Example 1, except that the concention. It is quite possible that some phenolic-type antioxtration ranges of AYP and HVP were decreased. Table 40 'idant materials which have not been permitted in foods 3 shows the induction periods (in hours) for the various in the past or which have been. used for a while and samples in which the concentrations of BHT and AYP then disapproved because of toxicities or questions of or HVP were varied. The synergism of the combmapossible carcinogenicity in higher concentrations may tions of antioxidants was calculated in the same manner as a result of the present invention become useful in as in Example I. foods in combinations with quantities of HVP or AYP TABLE 3 m AYP 0 3 5 10 BHT, LP. LP. Syn. |.P. Syn. LP. Syn.

' Mean Svn. 50.4

78 HVP 0 3 5 10 l.P. LP. Syn. "/1 LP. Syn. 1 P. Syn.

Mean Syn. 37.4

Although the invention has been described and illusof as much as 50 percent by weight of the oxidation susceptible materials in the product since HVP and AYP are non-toxic and their antioxidant characteristics may be synergized by very small amounts of such phenolictype antioxidants, amounts thereof which may be so small as to cause no concern about toxicity or other ill effects.

Although the invention has been described above in terms of the use of synergistic amounts of hydrolyzed vegetable protein, particularly hydrolyzed soy bean protein, or autolyzed yeast protein, as the protein derivative material employed in combination with a phenolic-type antioxidant in the stabilization of food products against oxidative degradation, it is to be understood that other sources of protein derivative materials .may be employed for producing the synergist to be used in combination with the phenolic-type antioxidant. Different protein degradation or breakdown products will not be equally effective as synergists for phenolic-type antioxidants since the proportions of var ious hydrolysis or other breakdown products will vary depending on the source of the protein and, furthermore, it is not known which of the various breakdown products of proteins are most responsible for the synergistic action which provides the basis of the present invention. It is, therefore, intended that the expression HVP includes hydrolyzed proteins from any vegetable sources which effectively synergize the antioxidant properties of phenolic-type antioxidants.

The synergistic antioxidant compositions of the invention are very useful for stabilizing food products against oxidation. They make possible considerable reductions in the concentrations of phenolic-type antioxidants in foods, thus markedly reducing the probabilities of harmful effects of such chemical additives on the health and well-being of consumers. In the present state of society, many food products require production long before they are consumed. Hence, they need to be pro by weight.

tected against oxidative degradation both for better nutrition and retention of desirable flavors, aromas, textures and the like. The present invention, making possible marked reductions in the amounts of synthetic antioxidants needed in food products to protect them for a reasonable length of time until they are consumed,

We claim:

- '1. A process for the stabilization against oxidation of oxidation susceptible foods, which comprises adding thereto an antioxidative amount of an antioxidant composition comprising (a) a compound selected from the group consisting of butylated hydroxyanisole, butylated hydroxytoluene, and a-tocopherol, and (b) autolyzed yeast protein, said autolyzed yeast protein being present in said antioxidant composition in an amount which is effective as a synergist for the antioxidant action of said compound selected from the group consisting of butylated hydroxyanisole, butylated hydroxytoluene, and or-tocopherol.

2. The process of claim 1, wherein said compound selected from the group consisting of butylated hydroxyanisole, butylated hydroxytoluene, and oz-tocopherol is added to said oxidation susceptible food in a concert-- tration of from about 0.0005 percent to about 0.05 percent by weight and said autolyzed yeast protein is added to said oxidation susceptible food in a concentration of from about 0.5 percent to about 50 percent 

1. A PROCESS FOR THE STABILIZATION AGAINST OXIDATION OF OXIDATION SUSCEPTIBLE FOODS, WHICH COMPRISES ADDING THERETO AN ANTIOXIDATIVE AMOUNT OF AN ANTIOXIDANT COMPOSITION COMPRISING (A) A COMPOUND SELECTED FROM THE GROUP CONSISTING OF BUTYLATED HYDROXYANISOLE, BUTYLATED HYDROXYLOTUENE, AND A-TOCOPHEROL, AND (B) AUTOLYZED YEAST PROTEIN SAID AUTOLYZED YEAST PROTEIN BEING PRESENT IN SAID ANTIOXIDANT COMPOSITION IN AN AMOUNT WHICH IS EFFECTIVE AS A SYNERGIST FOR THE ANTIOXIDANT ACTION OF SAID COMPOUND SELECTED FROM THE GROUP CONSISTING OF BUTYLATED HYDROXYANISOLE, BUTYLATED HYDROXYTOLUENE, AND A-TOCOPHEROL.
 2. The process of claim 1, wherein said compound selected from the group consisting of butylated hydroxyanisole, butylated hydroxytoluene, and Alpha -tocopherol is added to said oxidation susceptible food in a concentration of from about 0.0005 percent to about 0.05 percent by weight and said autolyzed yeast protein is added to said oxidation susceptible food in a concentration of from about 0.5 percent to about 50 percent by weight. 